Liver Damage From Alcohol
Scientists discover why liver may not heal after stopping alcohol
Introduction To Liver Regeneration
The liver is one of the most unique organs in the human body, with the ability to repair and rebuild itself after injury. However, excessive alcohol use can interfere with this process, leading to severe liver damage. Researchers at the University of Illinois Urbana-Champaign, Duke University, and the Chan Zuckerberg Biohub Chicago have made a groundbreaking discovery that sheds light on why the liver may not heal even after a person stops drinking. Their findings, published in Nature Communications, reveal that alcohol-related damage can leave liver cells trapped in an abnormal middle state, unable to function normally or complete the regeneration process.
The Liver's Regenerative Process
Under normal circumstances, the liver's regenerative process involves surviving liver cells temporarily changing their identity, multiplying, and then maturing again to restore lost tissue. This process is made possible by the liver cells' ability to reprogram which genes they use, allowing them to revert to a fetal-like progenitor state. Progenitor cells are less specialized cells that can divide and produce new tissue. After multiplying, the cells normally reverse that process and become mature, fully functioning liver cells again. However, in alcohol-associated liver disease, this regenerative cycle is disrupted, leading to liver failure.
What Goes Wrong In Alcohol-Associated Liver Disease
To understand what goes wrong in alcohol-associated liver disease, the researchers compared healthy liver samples with liver tissue from people with alcohol-associated hepatitis or cirrhosis. They found that cells in the diseased livers had started moving away from their mature state and toward the regenerative state, but they were unable to finish the transition. Instead, they remained trapped between the two, neither functional adult cells nor proliferative progenitor cells. This unproductive quasi-progenitor state leads to a damaging cycle, where more cells enter this state, fewer remain available to carry out the liver's normal work, and the remaining healthy cells face greater demands and attempt to regenerate, only to risk becoming trapped as well.
The Role Of Inflammation And RNA Splicing
The researchers found that inflammation plays a key role in disrupting the liver's regenerative process. Inflammation disrupts RNA splicing, an essential step cells use to turn genetic instructions into working proteins. RNA acts as an intermediary between the genetic code stored in DNA and the proteins that carry out cellular functions. The disruption of RNA splicing prevents liver cells from completing the regeneration process, leaving them trapped in the abnormal middle state. This discovery could point toward new ways to diagnose and potentially treat severe alcohol-associated liver disease.
Implications And Future Outlook
The findings of this study have significant implications for the diagnosis and treatment of alcohol-associated liver disease. Currently, the only real life-saving treatment option once a patient reaches the liver failure stage is transplantation. However, if researchers can understand why these livers are failing, they may be able to intervene and develop new treatments. The discovery of the role of inflammation and RNA splicing in disrupting the liver's regenerative process provides a potential target for future therapies. Further research is needed to fully understand the mechanisms underlying alcohol-associated liver disease and to develop effective treatments.
Sources
This is an original synthesis by Qivorane based on reporting from the outlets below.